γ-Stearolactone ring-opening by zeolites for the production of branched saturated fatty acids.

C branched saturated fatty acids (BSFA) are used as ingredients in cosmetics and lubricants and are produced the hydrogenation of C branched unsaturated fatty acids (BUFA). Industrial-grade C BUFA contain the odorous by-product γ-stearolactone (GSL), which must be removed by acid-catalysed ring-opening of GSL into oleic acid. Zeolites such as Y and beta can facilitate the ring-opening, but due to the dimensions of GSL the activity is expected to be limited by diffusion into the micropores.